Small Drip Irrigation System from hose bib

We just moved into a townhome with a very small yard. We would like to install a drip irrigation system from our hose bib that's on a simple timer. The more we looked, the more we became concerned with backflow prevention and 'continuous use' of the hose bib. Here are the concerns:

We have several hanging plants that we wanted to hook into the system. They are several (7 or so) feet above the hose bib (we also have a small hill in the yard that we'd like to irrigate, and topographically it is above the hose bib, also). It appears that the standard backflow prevention devices need the water source to be 6" above the highest sprinkler/drip emitter. Other backflow prevention devices look very big and very expensive. Is there a backflow prevention device that would work without breaking the bank (it's such a small system!)?

The 2nd concern is with our hose bib. It's a Woodford Model 17 Freezeless Wall Faucet (www.woodfordmfg.com/Woodford/Wall_Faucet_Pages/model-17.htm). On the website, the spec says that it is not rated for over 12 hours of continuous use. Does this mean we could not leave it continuously 'on' and have a timer (or other valve) downstream? If not, is there a way that we could have a timer downstream of this faucet while leaving it 'on' continuously?